RIVERHEAD - The man accused of gunning down four people at a Medford pharmacy appeared before a judge today and pleaded not guilty to the killings.

A grand jury indictment against David Laffer was unsealed in Riverhead, revealing that the 33-year-old Medford man was charged with five counts of first-degree murder: one count for each of the four victims, and an additional umbrella count stemming from multiple killings. Laffer also faces weapons charges.

Laffer stood surrounded by court officers as prosecutors laid out the details of what happened inside Haven Drugs on Father's Day.

According to officials, Laffer staked out the pharmacy the night before the incident.

Suffolk County District Attorney Thomas Spota says surveillance video shows Laffer walking into the pharmacy and having a light exchange with pharmacist Raymond Ferguson, after which Laffer could be seen killing him and 17-year-old employee Jennifer Mejia.

"Without any demands whatsoever for drugs or for money, he shoots Mr. Ferguson in the abdomen," Spota says.

According to prosecutors, Laffer was then spooked by two customers who entered the pharmacy, Bryon Sheffield and Jaime Taccetta, so he shot them one after another in the back of the head before proceeding to stuff drugs into his backpack.

Taccetta's fiancé, who was waiting for her in the parking lot, walked into the drug store just moments after Laffer walked out, prosecutors say.

Laffer's case is not back on the court calendar until September. If a plea deal is not reached beforehand, the judge says a jury will be picked in January.

If convicted, Laffer could face up to five life sentences without parole.

Associated Press reports contributed to this article.

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